68 A GEOLOGICAL HISTORY. 



ocean,* it will be found to be about 300 miles, 

 which is a rise of only about 100 feet, in every 

 fifty-four miles, or thereabouts. 



7th Shale.— (See plate 7, Jig. 7.) This Shale 

 belongs to the Onondaga salt group. 



8th Corniferous Limestone. — (See plate 7, Jig. 

 8.) This rock is a Limestone, with a large pro- 

 portion of Hornstone, which is a silicious mineral, 

 resembling flint in appearance, of the colour of 

 horn, from which it takes its name, I have seen 

 fossils in it completely silicated. 



9th Pyritiferous Rock (of Eaton.) — (See plate 7, 

 fig. 9.) This name seems to have been dropped 

 by the state Geologists. 



10th Shales of the Hamilton group. — (See plate 

 7, Jig. 10.) See table. 



11th Shells.— (-See plate 7, Jig. 11.) These 

 beds of shells consist of Unio's, Anodonta's, Me- 

 lania's and of other inhabitants of fresh water 

 lakes and streams ; they are found on top of the 

 highest ridges of Lewistown heights and on Goat 

 Island, and no doubt were left there when the 

 level of Lake Erie was much higher than it now 



* It is a great pity that the means could not be procured to build the 

 Erie and New York Railroad, the distance in a straight line is so short ; 

 and I am of opinion that the land and property holders of this city stand 

 greatly in their own light by not having the enterprize carried into effect. 



